| 摘要 |
An adjustable pedestal comprises a tubular base, a tubular collar telescopically, slidably engaging the exterior of the base, a guide tube interior to the base, an extension spring mechanism positioned within the guide tube for biasing the pedestal in an extended position, and a locking mechanism for locking the pedestal in the desired position. The base, collar, and guide tube are coaxial. The collar is movable between an extended and a retracted position with respect to the base, and the guide tube is movable with the collar between an extended and a retracted position with respect to the base. The extension spring mechanism comprises a pair of parallel, spaced-apart extension springs, the axes of which are parallel to the axes of the base, collar, and guide tube and normally biases the collar and the guide tube in their extended positions. The extension springs are in a retracted condition. Thus, when force is exerted on the top of the guide tube, the extension springs assume an extended condition. The guide tube is provided with a longitudinally-extending locking slot, and the locking mechanism comprises a locking block and a locking screw slidable in the locking slot.
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